WO 96/27544 discloses a device for transporting products between different stations. Here, a carriage is provided which has a U-shaped yoke, wherein permanent magnets are formed on the inner sides of the yoke. Within the yoke there are arranged multiple air-core coils which are seated on a support plate. When the air-core coils are electrically energized, a magnetic field forms, which magnetic field interacts with the magnetic field of the permanent magnets of the yoke such that the carriage is subjected to a translatory movement. The air-core coils form an air gap between the permanent magnets. Said gap must be kept small in order to achieve a good action of force. The mechanical strength opposes this and does not permit good strength. The mechanical guide cannot be combined with the coil arrangement in this way. Furthermore, air-core coils have the disadvantage of high magnetic leakage losses, in particular in the case of relatively large dimensions. In general, air-core coils are characterized by low inductivity, which leads to a lower thrust force for a given construction and mode of activation.
U.S. Pat. No. 6,876,107 B2 discloses a transport system. Here, a carriage having a U-shaped yoke is provided, wherein permanent magnets are arranged on inner sides of the U-shaped yoke. Within the U-shaped yoke there are formed two opposing coils. With corresponding energization of the coils, a magnetic field forms which interacts with the magnetic field of the permanent magnets such that the carriage performs a translatory movement. Owing to the high number of coils required, such a construction exhibits high complexity, which leads to high costs for the components and the cabling thereof etc. Furthermore, such a construction requires a considerable amount of installation space.
US 2008/0036305 A1 presents a linear motor comprising multiple core/winding units which each comprise a core composed of steel and a coil wound around the core. Here, the core/winding units are fastened to holding elements, wherein the holding elements themselves are fastened to a frame.
DE 690 03 365 T2 presents a linear motor comprising a stator. The stator comprises multiple coils which are tightly surrounded and held by fastening elements. Here, the fastening elements are manufactured from non-magnetic conductive materials such as, for example, aluminum. Also provided is a circuit board which is arranged horizontally on the upper end of the coils. Electronic control circuits for the coils are arranged on the circuit board.
JP 002000324789 A presents an air-core coil comprising a reinforcement element composed of plastic around which a coil is wound. The coil is an air-core coil. Furthermore, the reinforcement element has a protuberance which can be inserted into a hole of a substrate with electrical terminals.
The known systems are thus disadvantageous in particular in that they require a considerably large installation space and exhibit mechanical instabilities, which can for example lead to disturbing vibrations during operation. Furthermore, the known systems also have the above disadvantages described in conjunction with air-core coils.